Referring now to FIG. 1, a wireless local area network 10 is shown. A quality-of-service (QOS) enhanced wireless access point (QAP) 12 has a connection 14 to a distributed communications system (DCS) 16 such as the Internet. One or more QOS enhanced wireless stations 18-1, 18-2, 18-3, . . . , 18-N (collectively QSTAs 18), are in wireless communication with the QAP 12. The QSTAs 18 may include wireless telephone handsets that use a voice-over-internet protocol (VoIP). The QAP 12 provides each of the QSTAs 18 with a communication path to the DCS 16.
The QSTAs 18 can be battery poweredand employ a power saving mode to conserve power. When the power saving mode is enabled, the QSTAs 18 periodically enter a sleep mode, during which they are unable to communicate with the QAP 12. Therefore, each QSTA 18 sends a power save message to the QAP 12 before entering the power savings mode. In response to receiving the power save message, the QAP 12 buffers data destined for each QSTA 18 that has entered the power save mode. While in the power save mode, each QSTA 18 wakes up periodically, waits for access to the wireless channel, and then sends a polling message to the QAP 12. When the QAP 12 receives the polling message, it sends the buffered data to the polling QSTA 18. The QSTA 18 then reenters the sleep mode until its next scheduled wake up time.
Referring now to FIG. 2, exemplary power saving mode transmissions between the QAP 12 and one of the QSTAs 18 are shown. Prior to a time 50, the QSTA 18 is asleep in the power save mode. At the time 50, the QSTA 18 wakes up and executes a collision avoidance protocol during a time 51. The QSTA 18 then sends the polling message 52 to the QAP 12. In response to receiving the polling message 52, the QAP 12 sends packets of buffered data 54-1, . . . , 54-M to the polling QSTA 18. The QAP 12 sets a bit in the last packet of buffered data 54 to indicate an end of service period (EOSP) 56. Upon receiving the EOSP 56 indication, the QSTA 18 goes back to sleep until the cycle repeats at a time 58.
The QSTA 18 is in the sleep mode and conserving power between the EOSP 56 and the time 58. The QSTA 18 is awake and consuming full-power mode between the time 50 and the EOSP 56. It remains desirable in the art to reduce power consumption in the QSTAs 18.